Not applicable.
Not applicable.
The present invention relates generally to deformable seals for gates, and more particularly to a sealing apparatus for water and sewage treatment facility slide gates and sludge handling and dewatering system load-out slide gates.
Slide gates are widely employed to control fluid flow through fluid passages, especially in water and sewage treatment facilities and in dewatering and sludge handling environments. Slide gates typically comprise a frame having channels in which a slide gate door is mounted for selective movement to define either an opening or a closure. A seal of some kind is provided to create a watertight seal between the gate and the frame. An ideal seal minimizes frictional resistance to gate movement while maximizing seal durability and seal effectiveness.
While the art is not new, there have been many recent improvements in slide gate seal design. Exemplary and illustrative improvements are shown in the following U.S. Patents.
U.S. Pat. No. 4,226,553, to Whipps et al, shows a slide gate mechanism comprising a frame, a gate mounted to the frame and adapted for vertical movement to open or close the opening in the frame, actuating means for moving gate, and a seal mounted in the frame assembly for providing a watertight seal between the gate and the frame assembly when the gate is closed. The seal comprises a sealing member having an offset bulb portion and means for mounting the sealing member to the frame assembly.
U.S. Pat. No. 4,848,962, to Whipps, discloses a purported improvement over the sealing system of the earlier Whipps et al patent. What is shown is a slide gate having a frame assembly formed from interconnected extruded members formed with a substantially U-shaped channel, and a sealing member seated within the U-shaped channels. A side seal is seated in each side member of the frame assembly. Each side seal has a pair of U-shaped channels defining a double U-shaped channel formed by a pair of sidewalls with a common wall between the sidewalls. The common wall has a bulbous upper portion. The interior surface of one U-shaped channel has a lip seal in the form of a pair of inwardly extending lips that face the bulbous portion of the common wall. The slide gate is received in sealing engagement between the lip seal and the bulbous portion. The exterior sidewalls of each side seal has a plurality of barbed ribs which accommodate irregularities in the channels formed in the extruded frame assembly. A lower seal is seated in the bottom of the frame assembly for sealing the lower end of the slide plate when the slide plate is in its closed position. In certain applications, a horizontally extending upper seal in the form of an adjustable lip seal provides sealing contact between a top frame member and the slide plate.
In yet another patent to Whipps, U.S. Pat. No. 6,176,493 teaches a seal assembly for slide gates comprising a seal having a base section, and first, second and third mutually spaced sections integral with the base section. The first and second sections define a slide-receiving channel and the second and third sections define a tapered wedge-receiving channel. A tapered wedge member is disposition in the wedge-receiving channel. The seal and wedge are attached to a gate slide guide in such a fashion that the wedge is retained at a selected depth in the wedge-receiving channel. The seal is made of a material that allows the second section to flex away from the first section and toward the third section under a flexing force produced by the wedge member acting on the second and third sections, thereby causing the first and second sections of the seal to engage opposite surfaces of a slide disposed in the slide-receiving channel, with the first and second sections forming a watertight sliding seal with the inserted slide.
U.S. Pat. No. 4,700,927 to Henderson, teaches an open channel slide gate having a frame made up of parallel channel guides extending vertically from a horizontal bottom to define a gate opening. The channel guides have first and second guide flanges protruding laterally into the gate opening. A gate disc is supported by the frame for vertical movement between a lowered/closed position and an open position. The gate disc has side portions between the first and second guide flanges, and the side portions carry seal assemblies. Vertically spaced pivotal pressure pads are mounted on each of the channel guides between their respective first and second guide flanges. Adjustable mechanisms are employed to pivotally adjust the pressure pads to bear against the disc side portions when the disc is in its lowered position, with the result that the seal assemblies are compressed between the disc side portions and the first guide flanges. Each seal assembly comprises a flexible sealing element having an elongated body extending vertically along each disc side portion, with a pair of mutually spaced lips. A retainer bar extends along the sealing element between the lips. When the gate disc side portions are urged towards the first guide flanges as a result of the seating force generated by the pivotal pressure pads, the sealing lips deflect outwardly with respect to each other against the first guide flanges until those flanges contact the retaining bars.
The foregoing art is known to provide some advantages over the prior art; but it has not adequately addressed certain limitations in conventional slide gate seal design. Primary among the limitations in the prior art is the failure to provide means for pre-loading the seal so that a positive seal can be maintained at all times during the opening and closing of the gate. This configuration also serves as a superior cleaning function to maintain the sealing surface between the gate blade and the seal and ensures that the sealing surfaces of the gate and blade are not compromised by product intrusion.
The slide gate sealing system of the present invention incorporates numerous sealing concepts which, combined into a system, provides a positive, watertight seal for slide gates used in water and sewage treatment facilities and, more particularly, in a dewatering sludge handling application. The sealing system can be utilized in any shape or size of slide gate opening and is especially effective where the slide gate is heavily loaded by a large head of material. A gate of this type is described in pending U.S. Pat. No. 6,508,387, to the instant inventor and others, which is incorporated in its entirety by reference herein. The present inventive sealing system is also effective where there is a requirement that the slide gate provide a leak proof seal when the application calls for the slide gate to span a large distance in the transverse direction to the open and closed direction of the gate.
It is therefore an object of the present invention to provide a new and improved slide gate sealing system.
It is another object of the present invention to provide a new and improved slide gate seal that employs a ramping cam to pre-load a ball seal and thereby creates a watertight seal when the slide gate blade is in a closed position.
A further object or feature of the present invention is a new and improved slide gate sealing system that is easy to install, replace, and maintain.
An even further object of the present invention is to provide a novel slide gate sealing system that is inexpensive to manufacture and is amenable to easy dimensional modification for custom installations.
Other novel features which are characteristic of the invention, as to organization and method of operation, together with further objects and advantages thereof will be better understood from the following description considered in connection with the accompanying drawing, in which preferred embodiments of the invention are illustrated by way of example. It is to be expressly understood, however, that the drawing is for illustration and description only and is not intended as a definition of the limits of the invention. The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming part of this disclosure. The invention resides not in any one of these features taken alone, but rather in the particular combination of all of its structures for the functions specified.
There has thus been broadly outlined the more important features of the invention in order that the detailed description thereof that follows may be better understood, and in order that the present contribution to the art may be better appreciated. There are, of course, additional features of the invention that will be described hereinafter and which will form additional subject matter of the claims appended hereto. Those skilled in the art will appreciate that the conception upon which this disclosure is based readily may be utilized as a basis for the designing of other structures, methods and systems for carrying out the several purposes of the present invention. It is important, therefore, that the claims be regarded as including such equivalent constructions insofar as they do not depart from the spirit and scope of the present invention.
Further, the purpose of the Abstract is to enable the U.S. Patent and Trade-mark Office and the public generally, and especially the scientists, engineers and practitioners in the art who are not familiar with patent or legal terms or phraseology, to determine quickly from a cursory inspection the nature and essence of the technical disclosure of the application. The Abstract is neither intended to define the invention of this application, which is measured by the claims, nor is it intended to be limiting as to the scope of the invention in any way.
Certain terminology and derivations thereof may be used in the following description for convenience in reference only, and will not be limiting. For example, words such as xe2x80x9cupward,xe2x80x9d xe2x80x9cdownward,xe2x80x9d xe2x80x9cleft,xe2x80x9d and xe2x80x9crightxe2x80x9d would refer to directions in the drawings to which reference is made unless otherwise stated. Similarly, words such as xe2x80x9cinwardxe2x80x9d and xe2x80x9coutwardxe2x80x9d would refer to directions toward and away from, respectively, the geometric center of a device or area and designated parts thereof. References in the singular tense include the plural, and vice versa, unless otherwise noted.